Rotary kiln.



J. S. FASTING.

ROTARY KILN.

APPLICATION FILED JULY 27, 1910.

997,381, Patentd July 11,1911. 1

2 SHEBTSSHEET 1.

J. S."'FASTING.

ROTARY KILN.

APPLICATION IILED JULY 21,1910.

997,381. PatentedJuly 11,1911.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

JOHAN SIGISMUND FASTING, OF FREDERIKSBERG, NEAR COPENHAGEN, DENMARK,

ASSIGNOR TO F. L. SMIDTH & 00., OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

ROTARY 'KILN.

Patented July 11, 1911.

Application filed July 27, 1910. Serial No. 574,048.

To all whom it may concern:

Be it known that I, JOHAN SIGISMUND FAsTING, a subject of the King of Denmark, and a resident of F redericksberg, near Copenhagen, Denmark, have invented certaln new and useful Improvements in Rotary Kilns, of which the following is a specification, reference being had to the accompanying drawings, forming a part hereof.

This invention relates to rotary kilns for the burning of cement and other materials a and in which the powdered, gaseous or liquid fuel is supplied under pressure at the lower or discharge end of the kiln and in which the lower or discharge end of the kiln is closed during the burnlng by a closure which is movable in order to permit access to the interior of the kiln whenvnecessary. It is practically impossible to make the joint between the end of the kiln and the closure tight and the result is that when an attempt is made to use a forced draft tosupply the air which supports the combustion within the kiln, the pressure under which the air is supplied is necessarily limited by reason of the fact that when the pressure within the kiln much exceeds atmospheric pressure the hot gases escape between the end of the kiln and the closure and quickly burn away the iron plates with which they come in contact. The difficulty is overcome to some extent by carrying the stack or chimney to a height suflicient to give the requisite suction, but this involves expense and is otherwise objectionable.

It is the object of this invention to provide means for overcoming the difliculty referred to without requiring a lofty stack or chimney, and this object is attained by forming about the joint between the kiln and the closure a chamber to which air is supplied under such pressure as to prevent the escape of hot gases from the kiln through the 'oint. J The invention will be more fully explained hereinafter with reference to the accompanying drawings in which it is illustrated an in which- I Figure 1 is a view partly in outline and partly in section of so much of a rotary kiln and its appurtenances as is necessary to enable the application of the invention thereto to be understood. Fig. 2 is a similar view showing a slightly modified arrangement. Fig. 3 is a view in section, on a larger scale than Figs. Land 2, illustrating a further modification.

The kiln a is supported for rotation and may be rotated by any. usual or suitable means not necessary to be shown or explained herein. The closure 12 is supported in position against the lower or discharge end of the kiln, being represented in Figs. 1 and 2 of the drawings as mounted movably upon suitable wheels 0 and it is shown as provided with a suitable nozzle d through which the powdered, gaseous or liquid fuel may be introduced. The burned clinker or other material, discharged from the open directed into the cooler f, which is also preferably mounted so as to be rotated and may be provided at its discharge end, as shown in Figs. 1 and 2, with a chamber g, which may be opened from time to time to discharge the cooled clinker. A blower h is shown as connected with the chamber 9 by a pipe h which. may be provided with a damper k toregulate the admission of air to the chamber 9. The air which is thus supplied under pressure to the chamber 9 passes through the cooler f, absorbing heat from the clinker therein, and passes through the chute e,' and, it may be through the dust chamber e, into the interior of the closure 6 and thence intothe kiln a, thuscreating, in conjunction with the pressure of the powdered, gaseous or liquid fuel, which is pressure, the hot gases would be forced out from the interior of the kiln through the joint between the end of the kiln and the closure, which joint, under practical working conditions, cannot be made tight. The

escape of the intensely hot gases through the joint quickly causes the destruction of the iron plates with which such gases come in contact and in order to prevent the escape of such gases through the joint there is formed, in accordance with the present invention, an air chamber about the joint to which air is supplied under such pressure as is necessary to prevent the escape regulated in any suitable manner.

of the gases. This chamber may be arranged in various ways, as indicated in the several figures of the drawings.

Referringfirst to the arrangement shown in Fig. 1, the wall of the chamber In which Surrounds the joint between the kiln and the closure is assumed to be formed of metal plates, the front wall In being hinged or otherwise movable to permit the necessary movement of the closure 6, while the rear wall I: surrounds the kiln a between rings 70 so as to form a reasonably tight joint to prevent loss of air ressure. Air under pressure may be supp ied to the chamber is from any convenient source. As shown in Figs. 1 and 2, the blower k may be connected by a pipe h to supply the airunder pressure, such pipe being preferably provided with a regulating damper as indicated at h in Figs. 1,2 d3.

In the arran ement shown in Fig. 2, the wall is which orms the chamber 10' is represented as built mainly of brick, the rear wall being formed in art of an iron plate k so as to form with t e rings lo a reason- .ably tight joint about the kiln, while the front wall is provided with double doors is, through which-the workman may enter the chamber 70 when necessary.

In the arran ement shown in Fig. 3 the air chamber 70 is much reduced in size and is located wholly in rearof the closure 6. As there represented, it consists of an annular casing 70 supported at the rear of the closure 6. For the pur ose of forming a reasonably tight joint w1th the kiln the inner wall of the annular casing may be slotted to receive a ring 70 which may rotate with the kiln a while that portion of the wall It between the ring is and the closure may be perforated, as at is, to permit the passage of air into the subsidiary chamber around the joint between the end of the kiln and the closure.

The air pressure within the chamber 70 should be at least as great as the pressure within the end of the kiln and, if desired, it may be greater. The pressure may be As indicated in Figs. 1 and 2 the relative pressure of air in the chamber 70 and of the forced draft may be regulated easily by properly adjusting the dampers h and 72.

can have no destructive effect even if it should escape at'the joint.

It will be understood that the invention can be realized in many different forms of structure ada ted to special conditions ofuse and that 1t is not restricted to the articular arrangements shown and described herein. 1 p v I claim as my invention:

1. The combination with a rotary kiln and a closure therefor, of means for maintaining air under pressure about the joint between the kiln and the closure.

2. The combination with a rotary kiln and a movable closure therefor, of an air chamber surrounding the joint between the kiln and the closure and means for maintaining air under pressure within said chamber.

3. The combination with a rotary kiln and a movable closure therefor, of an air chamber surrounding the joint between the kiln and the closure, and means for supplying air under pressure to said chamber.

4. The combination with a rotary kiln and a closure therefor, of an annular chamber surrounding the joint between the kiln and the closure in rear of the closure, means for forming. a reasonably tight joint between the wall of the annular chamber and the kiln, and means for supplying air under pressure to said annular chamber.

5. The combination with a rotary kiln, 'a closure and a cooler, of an air chamber surrounding the joint between the kiln and the closure and a blower and connections for delivering air under pressure to the kiln through the cooler and to said air chamber.

This specification signed and witnessed this 21st, day of June A. D. 1910.

JOHAN SIGISMUND FASTING. Signed in the presence of-.

HERMANN Rim,

J ULrUs LEHMANN. 

